Student-faculty research uncovers secret to fruit fly mating

In science, discoveries and knowledge are built upon research. Here at Union, there is a large emphasis on research conducted by both professors and students.

Assistant Professor of Biology Roman Yukilevich is one of the professors involved in student-faculty research at Union. Professor Yukilevich and his crew, which usually consists of four or five students per term, are studying speciation.

Speciation is when a species of organisms diverges into two or more populations that are reproductively isolated from one another. These two groups eventually evolve on their own separate paths and become two independent species.

Professor Yukilevich’s goal is to look at recent divergences amongst species and to look for the causes of the divergence amongst those species. Professor Yukilevich wants to find the answer as to why certain members of a population develop different traits to the point that they are no longer capable of producing viable offspring with other members of the population. He also hopes to discover what, exactly, the cause of mating selection is, which is when different populations of the same species are no longer interested in one another.

In order to study speciation, Professor Yukilevich and his students have observed populations of the well-known Drosophila Melanogaster, colloquially referred to as fruit flies. These fruit flies come from all around North America.

The populations of fruit flies that Professor Yukilevich and his student research team are studying are all reproductively isolated from one another. Professor Yukilevich has compared the traits each group of fruit flies uses to select a mate, as well as the genetic architecture of those traits.

Due to the isolation from other populations across North America, each group of flies has its own specific traits that it searches for in a mate.

What Professor Yukilevich and his group of student researchers have discovered is that the flies sing songs to try to attract mates — and you music majors thought you were the only ones. What was most astounding to the research team was that the flies were reproductively isolated not because they could not produce viable offspring, but because they simply weren’t interested in flies from groups that had a different song than their own.

The findings indicate that this is an example of behavioral isolation, or pre-zygotic isolation, as opposed to post-zygotic isolation, in which offspring would be produced but would be infertile and thus useless for the survival of their species. While post-zygotic speciation is normally the product of genetic transformations, pre-zygotic speciation can often be caused by nothing more than a behavioral differentiation.

So what significance does this actually have? Mostly, the results raise more questions.

Why are the flies using the matin-song trait to select a mate? Is there some other trait attached to the song trait that allows flies to survive better in certain environments? Or is this just a case of xenophobia among the flies? More experimentation and observation will certainly be needed to find any answers to these questions. It may take a lot more work on the parts of Professor Yukilevich and his student researchers to discover what broader significance these results may have.

If you are interested in aiding professor Yukilevich in his research, gaining lab experience or studying genetics and animal behavior, reach out and contact him to become one of his five student researchers next term.